Gas lighter



M. QUERCIA l 3,533,720

GAS LIGHTER 3 Sheets-Sheet 1 oct. 13, 1970 Filed June 28 1968 lNveNroRfumata. @unc/A BY. mylar! f .$104, ATTORNEY l .P fri..

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Oct. 13, 1970 l M. QuERclA 35533720 n GAS LIGHTER v Filed June 2s 1968 YY s sheets-'sheet 2 INVENTOR HAMEL Galena/A ATTORNEY of13,197oMQU'ERCI', I 3,533,720

GAS LIGHTER Filed June 2e 196s J ,shatsv-snemv fla-b5.

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United States Patent O Inf. cl. rizsq 2/16 U.S. Cl. 431-277 20 ClaimsABSTRACT F THE DISCLOSURE A ring of leather, with its grain sidedirected towards the top and its flesh side towards the bottom, which ispierced at its centre Without removal of material, and through which acone of an adjusting screw is threaded whereby the ring rests on anannular surface at the base of this cone, can be clamped, by adjustmentof this screw, against a corresponding opposed annular surface providedwith a hole coaxial with the cone. By its compression, the ring limitsthe ow of the gas which, coming from the reservoir, passes through thisring before being able to escape towards the burner.

The present invention relates to a gas lighter with a reservoir,removable or not, for a liquefied combustible gas under pressure and anadjustable flow-restraining device, in which the gas, on its pathbetween the interior of the reservoir and a burner, is led to passbetween two clamping elements, between which is inserted aflowrestraining wad, and which can be clamped more or less tightly, onboth sides against this wad by setting an adjusting screw.

According to an important characteristic of this invention, the gasflow-restraining wad is made of leather, preferably natural, 'whichpresents two layers of different porosities, one of coarser porosity,situated, in the case of natural leather, on the inner side, also calledflesh side and the other, of liner porosity, situated on the outer side,also called grain side, the combustible gas, between the reservoir andthe burner, being led to pass successively through these two layers,preferably first the layer of coarser porosity oriented towards theupstream, and then the layer of finer porosity, oriented towards thedownstream, with respect to the direction of ow of the gas.

According to another important characteristic of the invention, therestraining wad is constituted by a ring of flexible material,preferably porous, pierced without removal of material and threaded on acone forming the central part of the annular clamping surface of one ofthese elements and projecting towards a gas passage orifice, provided inthe corresponding opposed clamping surface of the other element, theensemble being inserted in the gas outlet channel of the reservoir bythe peripheral side of the one of the faces of the ring and by thecentral orifice on its other face.

According to still another important characteristic of the invention,relating to the adjusting screw adapted to be set by the rotation of arotary member axially retained in the lighter, this member is coupled inrotation with this screw by means adapted to act in the manner of ascrew driver to cause, by the simple rotation of this member in onedirection or in the other, the screwing or the unscrewing of thisadjusting screw, the rotary member advantageously comprising anadjustable axial abutment, adapted to project 'by a greater or lesseramount with respect to the end of this member turned towards the abovementioned regulating screw and which, consequently, permits theadjustment of the extreme position adapted to be reached by theadjusting screw in the completely unscrewed position which correspondsto the maximum gas flow.

Other characteristics and advantages of the present invention willbecome apparent from the specic description of several embodiments ofthe invention, given merely by way of example, with reference to theaccompanying drawings in which:

FIG. l shows, partially in elevation, partially in axial section, a partof a gas lighter established according to a first embodiment of theinvention;

FIG. 2 shows, in axial section, a part of a lighter establishedaccording to another embodiment of the invention;

FIG. 3 shows, in axial section, a part of a lighter establishedaccording to still another embodiment of the invention; and

FIG. 4 shows, in perspective, a member forming part of the lighter ofFIG. 3.

Certain gas lighters present upstream of a lighter 1,

a gas flow-limiter, with which the user can himself adjust the height ofthe llame to his personal convenience.

This how-limiter generally comprises an adjusting wad 2, clamped betweentwo opposed surfaces 3 and 4, of adjustable separation, the wad and thesurfaces being inserted in such a manner, in the gas outlet channel,between a reservoir 5 of liquefied gas under pressure, removable or not,of the lighter, and a burner 1, that by moving one of these surfacestowards or away from the other, a decrease or an increase respectivelyis obtained of the flow of the gas issuing from the burner 1.

According to an important characteristic of the invention, the wad 2 ismade of leather presenting two layers of different porosities, one 2a,denser, of finer porosity, located in the case of natural leather on theouter side, also called grain side, and the other 2b, of coarserporosity, on the inner side, also called liesh side; the gas containedin the reservoir 5 must pass successively through these layers beforebeing able to leave this reservoir by the burner 1.

The =wad 2 is preferably made of natural leather, in particular of goatsleather, but it can, of course, also be made of synthetic leatherprovided that this leather presents the two layers mentioned above ofdifferent porosities.

The wad 2 is advantageously inserted in such a manner in the gas outletchannel that the gas can only leave the reservoir -5 by passing throughiirst the layer of coarser porosity 2b, oriented towards the upstream,and then, the layer of finer porosity 2a, oriented towards thedownstream with respect to the direction of flow of the gas.

According to the embodiment shown in FIG. 1, the reservoir 5 contains atube 6 which passes through it in a fluid-tight manner, this tubeopening on two opposite walls 5a, 5b ofthe reservoir.

At the interior, the tube 6 presents an intermediate annular shoulder6a. On one side of this shoulder 6a, the part 6b of the tube 6 containsa coaxial gas outlet control valve 7 which a return spring 8 applies ina fluid-tight manner against the edge of the central hole 9 of thisshoulder and whose tubular control rod 10, serving as a gas outletconduit, can form in a manner known in itself, by its free end, theburner 1.

In the part 6c of the tube 6 situated on the other side of the shoulder6a which, on this side forms one of the clamping elements of the wad 2,is screwed the other clamping element 11 whose head 11a, forming asetting member, projects out of the end of the tube 6 and projectsbeyond the face 5b of the reservoir.

An annular sealing joint 12, inserted between the screw 11 and the tube6, ensures the sealing downstream of an opening 13 provided radiallythrough the wall of the tube 6 and opening in this tube under the wad 2.

In this arrangement, when the valve 7 is lifted, by a mechanism known initself, the gas contained under pressure in the reservoir can passthrough the opening 13 in the tube 6, under the wad 2, pass through thiswad, then issue through the central hole 9 in the part 6b of the tube,to penetrate through a radial hole 14 in the tubular rod 10 and issue atthe end of this rod through the burner 1.

By screwing more or less tightly the clamping element 11 in the tube 6,the wad 2 is compressed 'more or less tightly, and consequently, theflow of the gas leaving the reservoir through this wad or between thesides of this wad and its clamping surfaces is decreased or increased.

It will be noted that the wad 2, made of leather, according to onefeature of the present invention, presents, by its two differentporosities, not only advantageous properties in themselves forrestraining the flow, but also the advantage of not becoming shabby whenit is urged in opposite directions by the two clamping surfaces 3 and 4turning one with respect to the other during the clamping of the wad.

Whether it is made of leather, or of any other flexible and/ orelastomeric material, whether it is porous or not, the wad 2 isadvantageously established in the form of a ring pierced at its centrewithout removal of material and threaded on a cone 15, forming thecentral part of the annular clamping surface 4 of the screw 11 andprojecting towards the hole 9, provided in the centre of thecorresponding clamping surface 3 of the tube 6.

Thus, an increase of the clamping of the ring 2 by screwing the element11 in the tube 6, produces in the thickness of the ring 2 a compressionwhich, more quickly than elsewhere, increases near the cone 15, andparticularly in the neighbourhood of the inlet of the hole 9, that is tosay in an annular zone of the ring through which the gas, coming fromthe reservoir 5, must necessarily pass before being able to arrive atthe valve 7 In this manner, a determined reduction of the gas flow canbe obtained with a minimum stress, since instead of being uniformlydistributed in the entire thickness of the ring 2, the compression ofthis ring is essentially limited to the region where it is effective forlimiting the flow of gas.

This adjustment of the gas flow by an accentuated compression of thering at its centre is particularly effective with porous rings, notablymade of leather.

Nevertheless, this Same type of adjustment is conceivable with rings ofother materials, for example with a ring in a flexible, evenfluid-tight, material, in which case the gas, instead of passing throughthe material of the ring, would have to pass along the clamping surface4 and go up along the surface of the cone 15 to the hole 9 between thering and these surfaces.

The ring 2 is advantageously fitted in a housing whose bottom is formedby the surface 3 with the central hole 9, whereas the clamping surface4, adapted to penetrate into this housing there to compress the ring 2extends to the neighbourhood of the periphery of this housing whileallowing an annular slot to remain, along this periphery, for thepassage of the gas through the ring 2.

This annular slot is advantageously obtained by a chamfer 16 at theperiphery of the frontal clamping surface 4 of the screw 11, the opening13 being provided through the part 6c of the tube 6 so that it opensopposite to this chamfer 16.

Thus, the gas under pressure coming from the reservoir 5, can, bypassing through the opening 13, reach the periphery of the lower surfaceof the ring 2, which obliges it, in order to reach the opening 9, whenthe Valve 7 is raised, to pass through the porous ring 2 from one sideto the other.

The reservoir 5 can, of course, be completely filled with 4 materialadapted to absorb the liqueed gas under pressure that it contains.

In the case in which the reservoir 5 is traversed from one end to theother by a tube 17, parallel to the tube 6, which tube 17 can inparticular serve for receiving the ignition flint and its spring, it isadvantageous to make the opening 13 open into the reservoir 5, betweenthese two tubes, so that its cross section is divided, by the planecommon to the axes of the tubes 6 and 17, into two parts at leastapproximately equal, whose edges are separated as little as possiblefrom that plane, and to insert between these two tubes a tampon B ofmaterial adapted to absorb the liquid gas which is thus applied againstthe opening 13 with a maximum pressure, localized along the generatricesdetermining the minimum distance between the two tubes.

The rest of the reservoir can then be left empty of any stuiling, thusincreasing the capacity for receiving a greater quantity of liquefiedgas under pressure.

In the adjusting screw 11 is advantageously provided a filling valve 18,mounted in a blind axial channel 19 of the screw 11, which communicateswith the interior of the reservoir 5 through a radial channel 20 openingin the part 6c of the tube 6, upstream of the joint 12, preferablyopposite the opening 13, so that this opening can be traversed not yonlyby the gas under pressure leaving the reservoir, when the gas outletvalve 7 is raised, but also by the gas coming from a recharging nippleconnected to the head 11a, provided with a hole at 21, of the screw 11,on passing through the filling valve 18.

In a lighter established according to a variant represented in FIG. 2,the constituent parts which correspond by their structure or by theirfunction to those of the lighter represented in FIG. l, are designatedby the same reference numerals, but increased by 100.

According to this embodiment, the adjusting screw 111 for adjusting theheight of the llame, which does not con tain either valve or channel forfilling the reservoir and whose end remote from the cone is still at theinterior of the tube 106, is set by the rotation of a separate rotarymember 23 which covers the tube 106 on the exterior face 10519 of thelighter and which is axially retained in this tube by lugs 24, radiallyflexible and hooked into a groove 25 provided in the interior peripheryof the tube 106.

By this hooking, the member 23 is axially immobilized with respect tothe tube 106 but can turn at will in the two directions with respect tothis tube.

The member 23 is coupled in rotation with the screw 111 by means adaptedto act in the manner of a screw driver which permit, by the simplerotation of this member in one direction or in the other, the screwingor unscrewing of the screw 111 in the tube 106.

In the case represented, these coupling means comprise on the rotarymember 23 an axial tongue 26 and, in the screw 111, a diametrical slot22 in which the tongue 26 slides, thus penetrating into this slot by agreater of lesser amount during the common rotation of the member 23 andof the screw 111 which, in the course of this rotation, is screwed orunscrewed in the tube 106.

The tongue 26 and the corresponding slot 22, for the rotary coupling ofthe member 23 and the screw 111, can be replaced by other pairs ofprojections and hollows, provided that these corresponding projectionsand hollows form cylinders in the direction of the common axis of thescrew 111 and of the tube 106, without however being of revolution aboutthis common axis. Their cross section can in particular be polygonal.

The inlet of the tube 106 is preferably flared outwardly in the form ofa cone 27 which facilitates putting the member 23 in place, due to thefact that, when then lugs 24 are pushed axially in the cone 27, theybend towards the axis and, then, right themselves again elastically,when their end projecting towards the periphery has been able topenetrate into the groove 25, to hook there with the member 23.

In any case, when the user ofthe lighter unscrews completely theadjusting screw 111 by the rotation of the member 23, hel obtains aflame of maximum length.

With the ensemble represented in PIG. 2, the stroke of maximumunscrewing of the screw 111 in the tube 106 is difficult to determinewith precision, so that it can happen that the maximum length of the ameis too great and that a desastrous blow-pipe effect is then produced.

To remedy this disadvantage and to permit the manufacturer to proceedeasily, in the factory, with a precise adjustment of the maximum lengthof the flame, adapted to be obtained by the user when he sets the rotarymember 23, it is advantageous to provide on this rotary member 23,according to still another important characteristic of the invention, anadjustable axial abutment adapted to project to a greater or lesserdegree with respect to the end of the rotary member 23 turned towardsthe adjusting screw 111.

In this manner, by acting on this adjustable axial abutment, themanufacturer will have the possibility of adjusting the extreme positionadapted to be reached by the adjusting screw 111 when the user unscrewsthis adjusting screw completely, in Iwhich extreme position the end ofthe adjusting screw 111 oriented towards the rotary member 23 abutsagainst this axial abutment.

An advantageous embodiment of such an adjustable abutment is shown inFIGS. 3 and 4 in which various parts of the lighter fullling analogousfunctions to those shown in FIG. 2 have been designated by the samereference numerals increased by one hundred, the rotary member 123 beinghere axially retained in the tube 206 by an expansible split ring 28 andthe adjusting screw 211 acting by its end on a push-piece 29 of a device(not shown) for restraining the flow of gas.

According to this latter embodiment, the adjustable axial abutment,carried by the setting member 123, comprises, in an axial hub 123a ofthis member, a tapping 123b, and, screwed in this tapping, a screw 30 ofsufficient length to project to a greater or lesser extent above theupper end of the hub 123a of the member 123, the rotary coupling tongue126 having the form of an upside down U, in order to straddle the end ofthe screw 30, this screw nevertheless projecting out at both ends fromthis tongue, so that itsy projecting parts can effectively play the roleof axial abutments for the adjusting screw 211. After the adjustment ofthe abutment screw 30, which is carried out, as already indicated, bythe manufacturer or by a specialized workshop in the case of areadjustment, it is advantageous to seal the bore 123b, on the outerside, by a sealing and blocking wad 31, for example of plastic material,this wad preventing the user from having access to the screw 30.

The rotary member 23` or 123, by its part accessible from the exterior,can be very fiat or even embedded in the bottom of the lighter, in whichcase it is appropriate either to make it project slightly at itsperiphery out from each side of this bottom, or to provide it, in itsface directed towards the exterior, with a diametrical groove 32 (FIG.3) in which the user can insert a coin thus using it as a screw driver.

' Although the present invention has been described with particularreference to specific embodiments, various modifications and variationsare possible without departing from the spirit or scope of the presentinvention.

What I claim is:

1. A gas lighter including a reservoir for combustible gas, a burner, agas channel leading from said reservoir to said burner and an adjustablegas flow restraining device disposed in said gas channel for restrainingthe iiow of gas from said reservoir to said burner, in which said gasflow restraining device comprises two clamping elements between whichthe gas is led to pass on its path from said reservoir to said burnerand between which is inserted a flow restraining wad, one of saidclamping elements being operatively associated with an adjusting screwwhereby said two clamping elements are adapted to clamp said wad onopposite sides thereof with an adjustable degree of pressure determinedby the setting of said adjusting screw,

wherein said wad is made of leather having two layers of differentporosities, namely a layer of coarser porosity and a layer of finerporosity, said gas on its path between said reservoir and said burnerbeing led to pass successively through said two layers of said wad.

2. A lighter according to claim 1,

wherein said wad is made of natural leather, said layer of coarserporosity being situated on the inner side, also called flesh side, ofthe leather, and said layer of liner porosity being situated on theouter side, also called grain side, of the leather.

3. A lighter according to claim 1,

wherein in said gas channel leading from said reservoir to said burner,said leather wad is disposed with its coarser porosity oriented towardsthe upstream and its finer porosity directed towards the downstream withrespect to the flow of said gas.

4. A lighter according to claim 1,

wherein one of said clamping elements comprises a clamping surface atthe centre of which is provided an orifice for the passage of gas; theother of said clamping elements comprises a corresponding opposedclamping surface, annular in form, at the centre of which is disposed acone, constituting the central part of said annular clamping surface,said said cone projecting towards said orifice in said one clampingelement; and said ow restraining wad is constituted by a ring of exiblematerial, pierced without removal of material, and having said conethreaded through said ring.

5. A gas lighter including a reservoir for combustible gas, a burner, agas channer leading from said reservoir to said burner and an adjustablegas fiow restraining device disposed in said gas channel for restrainingthe flow of gas from said reservoir to said burner, in which said gasflow restraining device comprises two clamping elements between whichthe gas is led to pass on its path from said reservoir to said burnerand between which is inserted a iiow restraining wad, one of saidclamping elements being operatively associated with an adjusting screwwhereby said two clamping elements are adapted to clamp said wad onopposite sides thereof with an adjustable degree of pressure determinedby the setting of said adjusting screw,

wherein one of said clamping elements comprises a clamping surface atthe centre of which is provided an orifice forthe passage of gas; theother of said clamping elements comprises a corresponding opposedclamping surface, annular in form, at the centre of which is disposed acone, constituting the central part of saidannular clamping surface,said cone projecting towards said orifice in said one clamping element;and said flow restraining wad is constituted by a ring of flexiblematerial, pierced without. removal of material, and having said conethreaded through said ring.

6. A lighter according to claim 5,'wherein said wad is constituted by aporous material having two layers of different porosities, namely alayerof fine porosity and a layer of coarse porosity, said wad being disposedsuch that the gasV on its path between the reservoir and the burnerpasses successively first through the layer of coarse porosity and thenthrough the layer of fine porosity.

7. A lighter according to claim 6,

wherein the clamping surface with the central orifice forms the bottomof a housing in which said wad is fitted, whereas the other clampingsurface is adapted to penetrate into said housing, there to compresssaid wad, and extends to the neighbourhood of the periphery of saidhousing, while leaving an annular slot along said periphery for thepassage of gas through said wad.

8. A lighter according to claim 4,

wherein said reservoir is traversed from one end to the other by twoparallel tubes each fixed to opposite end walls of said reservoir, oneof said tubes being adapted to receive an ignition ilint and a springfor said ignition flint, and the other of said tubes being adapted toreceive said gas ow restraining device,

and wherein, on the one hand, the latter of said tubes is provided witha gas outlet opening which opens in the reservoir between said two tubesand whose cross-section is divided, by the plane common to the axes ofsaid two tubes, into two at least substantially equal parts, whose edgesare separated as little as possible from said plane, and on the otherhand, a tampon of material adapted to absorb the liqueed gas is insertedbetween said two tubes opposite to said gas outlet opening.

9. A gas lighter including a reservoir for combustible gas, a burner, agas channel leading from said reservoir to said burner and an adjustablegas ilow restraining device disposed in said gas channel for restrainingthe ow of gas from said reservoir to said burner, in which said gas flowrestraining device comprises two clamping elements between which the gasis led to pass on its path from said reservoir to said burner andbetween which is inserted a tiow restraining wad, one of said clampingelements being operatively associated with an adjusting screw wherebysaid two clamping elements are adapted to clamp said wad on oppositesides thereof with an adf justable degree of pressure determined by thesetting of said adjusting screw,

wherein said reservoir is traversed from one end to the other by twoparallel tubes each iixed to opposite end walls of said reservoir, oneof said tubes being adapted to receive an ignition flint and a springfor said ignition int, andthe other of said tubes being adapted toreceive said gas ow restraining device,

and wherein, one the other end, the latter of said tubes is providedwith a gas outlet opening which opens in the reservoir between said twotubes and whose crosssection is divided, by the plane common to the axesof said two tubes, into two at least substantially equal parts, whoseedges are separated as little as possible from said plane, and on theother end, a tampon of material adapted to absorb the liquefied gas isinserted between said two tubes opposite to said gas outlet opening.

10. A lighter according to claim 4,

wherein said reservoir is traversed in a uid-tight manner by a tubewhich opens at the exterior through two opposite walls of saidreservoir, said tube being provided, at its interior, with an interiorannular shoulder, and one one side of said shoulder, was a gas outletcontrol valve, and on the other side of said shoulder, with saidadjusting screw, said adjusting screw being adapted to adjust the llowof the gas capable of passing from said reervoir through a part of saidtube to said valve, and said adjusting screw having a head whichprojects out from one end of said tube to serve as a flow adjustingmember,

and wherein a filling valve is mounted coaxially in said adjustingscrew, said lling valve communicating with the interior of the reservoirthrough a blind axial channel provided in said adjusting screw andthrough two radial channels provided in correspondence in said adjustingscrew and in said tube respectively, downstream of an annular jointensuring a seal between said adjusting screw and said tube.

11. A gas lighter including a reservoir for combustible gas, a burner, a`gas channel leading from said reservoir to said burner and anadjustable gas flow restraining device disposed in said gas channel forrestraining the ow of gas from said reservoir to said burner, in whichsaid gas flow restraining device comprises two clamping elements betweenwhich the gas is lead to pass on its path from said reservoir to saidburner and between which is inserted a ow restraining wad, one of saidclamping elements being operatively associated with an adjusting screwwhereby said two clamping elements are adapted to clamp said wad onopposite sides thereof with an adjustable degree of pressure determinedbythe setting of said adjusting screw,,

wherein said reservoir is traversed in a fluid-tight manner by a tubewhich opens at the exterior through two opposite walls of saidreservoir, said tube being provided, at its interior, with an interiorannular shoulder, and on one side of said shoulder, with a gas outletcontrol valve, and on the other side of said shoulder, with saidadjusting screw, said adjusting screw being adapted to adjust the flowof the gas capable of passing from said reservoir through a part of saidtube to said valve, and said adjusting screw having a head whichprojects out from one end of said tube to serve as a ow adjustingmember, and wherein a lling valve is mounted coaxially in said adjustingscrew, said iilling valve communicating with the interior of thereservoir through a blind axial channel provided in said adjusting screwand through two radial channels provided in correspondence in saidadjusting screw and in said tube respectively, downstream of an annularjoint ensuring a seal between said adjusting screw and said tube. 12. Alighter according to claim 10, wherein said radial lling channel,provided in said tube traversing said reservoir, communicates with saidow restraining device which the gas must pass through before being ableto escape from said reservoir. y13. A lighter according to claim 4,wherein said adjusting screw and a rotary settlng member, which isaxially retained in said lighter, are coupled together in rotation bymeans adapted to act in the manner of a screw driver to cause, by thesimple rotation of said member, the setting of said adjusting screw. 14.A gas lighter including a reservoir for combustible gas, a burner, 1agas channel leading from said reservoir to said burner and an adjustablegas ow restraining device disposed in said gas channel for restrainingthe flow of gas from said reservoir to said burner, in which said gas owrestraining device comprises two clamping elements between which the gasis led to pass on its path from said reservoir to said burner andbetween which is inserted a flow restraining wad, one of said clampingelements being operatively associated with an adjusting screw wherebysaid two clamping elements are adapted to clamp said wad on oppositesides thereof with an adjustable degree of pressure determined by thesetting of said adjusting screw,

wherein said adjusting screw and a rotary setting member, which isaxially retained in said lighter, are coupled together in rotation bymeans adapted to act in the manner of a screw driver to cause, by thesimple rotation of said member, the setting of said adjusting screw. 15.A lighter according to claim 13, wherein said flow restraining adjustingscrew is screwed in a tube which traverses in a fluid-tight manner saidgas reservoir, said tube having an orifice by which it opens towards theexterior, on the side of said reservoir remote from said burner, whichorifice is obturated by said rotary setting member, which member ismounted free in rotation and retained axially in said tube. 16. Alighter according to claim 15, wherein said side of said reservoirremote from said burner is the bottom of said reservoir. 17. A lighteraccording to claim 16, wherein said rotary setting member carries anadjustable axial abutment adapted to project by an adjustable amount outof the end of said member facing said adjusting screw of said gas owrestraining device, said axial abutment, by the adjustment of the amountof its projection, adjusting the extreme position that said adjustingscrew can reach when it is completely unscrewed, in which extremeposition the gas flow is maximum.

18. A lighter according to claim 17,

wherein said rotary setting member comprises a disc provided with a hubbearing said axial abutment.

19. A lighter according to claim 1-8,

wherein said hub bears a tongue in the form of an upside down U, adaptedto play the role of screw driver with respect to said adjusting screw.

References Cited UNITED STATES PATENTS 3/1965 `Genoud 431-277 7/ 1968Wieden et al 431--344 9/ 1968 Koizumi 431-344 EDWARD G. FAVORS, PrimaryExaminer U.S. C1. X.R.

